Berlin, New Hampshire

Berlin, NH Accessory Dwelling Unit (ADU) Rules

City Acceptance Rating: 5/10

Last Updated: 8.28.2024

Image Source: NH PBS

What You Need To Know

To increase housing options while preserving neighborhood aesthetics, attached ADUs are permitted by the Planning Board through a Conditional Use Permit

Type of ADU Permit Required

Attached ADUs are permitted by the Planning Board through a Conditional Use Permit.

ADU Rules

  • One ADU Per Property: Only one ADU is allowed per property, and it is not permitted on properties with more than one primary dwelling unit (PDU).

  • Location: The ADU must be within or added to an existing or proposed single-family dwelling.

  • Self-Sufficient Living Quarters: The ADU must have its own sleeping, bathing, and eating facilities.

  • Exterior Changes: Exterior alterations to the PDU are allowed to accommodate the ADU but must not make the PDU look like a duplex or multifamily structure. Access ways should be placed at the side or rear of the building. The ADU should remain functionally dependent on the PDU, with no separate utilities, garages, or driveways. The ADU may have up to two bedrooms.

  • Size: The ADU must be no larger than 1,000 square feet and must not exceed 40% of the living area of the PDU.

  • Internal Connection: The ADU must be internally connected to the PDU.

  • Owner Occupancy: The property owner must live in one of the two units.

  • Parking: One additional parking space for the ADU must be provided if space is available on the property.

  • No Separate Ownership: The PDU, ADU, and lot cannot be converted to separate legal ownership. A restrictive covenant must be recorded in the Coos County Registry of Deeds, with copies provided to the Community Development Department and the Assessor before a Certificate of Occupancy is issued.

  • Septic Requirements: If municipal sewer service is unavailable, the septic system must meet NH Water Supply and Pollution Control Division standards for the combined occupancy of the property.

Resources:

https://www.berlinnh.gov/sites/g/files/vyhlif2811/f/uploads/chapter_17_zoning_ordinance_4-17-23_0.pdf#:~:text=A%20maximum%20of%20one%20(1,3.

Attached ADU, Convert Existing SpaceDeanna DuffeyNew Hampshiure, Berlin, Friendliness Rating 5/10